向东一定要用正数表示,向西一定要用负数表示.______.
由正、负数的意义可知:向东一定要用正数表示,向西一定要用负数表示,说法错误.
故答案为:错误.
根据汉语提示完成句子。
Today is Sunday. Look! This is my schedule.
I __________________ (打扫卧室) at 7: 00 a. m.
I __________________ (洗衣服) at 8: 00 a. m.
I __________________(扫地) at 9: 00 a. m.
I __________________ (倒垃圾) at 10: 00 a. m.
I __________________ (擦窗户) at 11: 00 a. m.
锌投入稀盐酸中.